Practice Exam 2, Problem 2: The Assembly Bridge

Midterm 1 practice exam 2, problem 2 of 5 · Length: 12:13 · Exercises: 20a_asm_bridge (Week 6) · Answer key: Solutions (PDF)

Worked on pages 6 to 10, with the two RISC-V tables and the code beside each part: (a) bytecopy traced over three bytes, and why a sign-extending load does not spoil the copy; (b) bytecopy edited into wordcopy, its registers on return, which registers a caller may still rely on, and why a leaf can skip the stack; (c) baby_swtch between the test and co_entry: the registers at two moments, what each Ctx holds, and what a new field at the top of Ctx breaks. The answer key's handwriting is written onto the exam page as each step is worked.

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